What I did before the crash:

1. run cargo init
2. run pijul init in folder
3. add src/main.rs and Cargo.toml
4. record change forgetting to set Authors field (~/.config/pijul/config.toml not yet setup)
5. fix email address in Cargo.toml
6. setup ~/.config/pijul/config.toml
7. record new change
8. fork tmp channel from first change
9. switch to tmp channel
10. run pijul record --amend and fill in Authors
11. run pijul push --to-channel main .
12. run pijul channel switch main, which resulted in the crash

The steps above are probably missing some thing as I am unable to reproduce the crash. After the crash pijul channel showed that the working directory was now on the main channel

name = 'pijul'
operating_system = 'unix:Unknown'
crate_version = '1.0.0-alpha.21'
explanation = '''
Panic occurred in file '/home/bennet/.cargo/registry/src/github.com-1ecc6299db9ec823/libpijul-1.0.0-alpha.18/src/fs.rs' at line 298
'''
cause = '''
assertion failed: inode.is_root() ||
    txn.del_tree(file_id.as_file_id(), Some(inode)).map_err(FsError::Txn)?'''
method = 'Panic'
backtrace = '''

   0: 0x5564849f8000 - libpijul::output::output::output_repository::h7a591bf165384d35
   1: 0x55648496b768 - pijul::commands::reset::Reset::reset::h56e3c00003c523d3
   2: 0x5564849900a2 - pijul::commands::channel::Channel::run::he41253454cbb5428
   3: 0x556484a71449 -  as core::future::future::Future>::poll::hd58a59fad351c664
   4: 0x5564848c6c50 - tokio::runtime::enter::Enter::block_on::h5c5f0c236d76dc6b
   5: 0x556484985f6d - tokio::runtime::thread_pool::ThreadPool::block_on::hdf8498896066a38e
   6: 0x5564849663cc - tokio::runtime::context::enter::h203b49ab005ba120
   7: 0x5564848d6645 - pijul::main::h38d1b94d672dc695
   8: 0x556484a02ed3 - std::sys_common::backtrace::__rust_begin_short_backtrace::ha6f34f232102fef1
   9: 0x55648494e509 - std::rt::lang_start::{{closure}}::h06cbf468ee028a2f
  10: 0x55648507ce97 - core::ops::function::impls:: for &F>::call_once::he179d32a5d10d957
                at /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/core/src/ops/function.rs:259
                 - std::panicking::try::do_call::hcb3d5e7be089b2b4
                at /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/std/src/panicking.rs:381
                 - std::panicking::try::h7ac93b0cd56fb701
                at /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/std/src/panicking.rs:345
                 - std::panic::catch_unwind::h7b40e396c93a4fcd
                at /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/std/src/panic.rs:382
                 - std::rt::lang_start_internal::h142b9cc66267fea1
                at /rustc/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/library/std/src/rt.rs:51
  11: 0x5564848d6772 - main
  12: 0x7efe038e50b3 - __libc_start_main
  13: 0x5564848742ce - _start
  14:        0x0 - '''

This was fixed by #IM6UFPOZHZTBMESRXGBALOAWJWUUDGLP2TVLSZ3RZPSJITKB3R7QC.